[history-substring-search] Fix incompatibility with zle-line-init widget
[history-substring-search] Fix incompatibility with zle-line-init widget

See https://github.com/zsh-users/zsh-history-substring-search/issues/70
and comment by @molovo:

     I was already binding keys _after_ `zle-line-init`, but I'm pulling
     keycodes out of the `terminfo` module, which reports up
     (`$terminfo[kcuu1]`) as `^[0A` instead of `^[[A`. Binding `^[[A`
     manually mean up/down works with history-substring-search both
     before and after `zle-line-init`, but if I bind `$terminfo[kcuu1]`
     (`^[0a`), up/down only works *before* `zle-line-init`.

Closes #286

joshuarubin/dotfiles,joshuarubin/dotfiles,Eriner/zim,joshuarubin/dotfiles,joshuarubin/dotfiles